LONG-TERM AGING EFFECT ON THE CRACK GROWTH IN THE MAIN CIRCULATING PUMP CASING MATERIAL

作者：Xue, F.^*; Yu, W. W.; Yu, M.; Liu, W.; Shu, G. G.

来源：Strength of Materials, 2015, 47(1): 100-107.

DOI：10.1007/s11223-015-9634-2

• crack growth
• thermal aging
• main pump casing
• AP1000 reactor

Fatigue crack growth (FCG) tests on the main circulating pump casing material were conducted at room temperature to investigate the effect of long-term aging at 400 degrees C. It was found that the FCG rate increased with aging time. However, there were similar Delta K-th values for both the virgin material and aged material at the same stress ratios R. At room temperature, Delta K-th was observed to decrease with an increase in R. An equation incorporating the K-max and Delta K effects was proposed to describe FCG rates over the linear portion of the curve (Paris equation) for all stress ratios. Additionally, fatigue fracture patterns near crack initiation sites reveals quasi-cleavage fracture in thermally aged specimens.

• 出版日期2015-1
• 单位清华大学